The US President warned the Democrats “two can play that game” after their victory in the House threw up the chance of investigations into his tax returns, businesses and administration by Democratic lawmakers.
But in a warning to his rivals, Mr Trump tweeted: “If the Democrats think they are going to waste Taxpayer Money investigating us at the House level, then we will likewise be forced to consider investigating them for all of the leaks of Classified Information, and much else, at the Senate level. Two can play that game!”
Democrats rode a wave of dissatisfaction with the American leader to win control of the US House of Representatives, giving them the opportunity to block Mr Trump’s agenda and open his administration to intense scrutiny.
READ MORE: Midterm elections results: Donald Trump vows to GET TRADE DEALS DONE
Nancy Pelosi, leader of the House Democrats, told supporters at victory party: “Today is more than about Democrats and Republicans, it’s about restoring the Constitution’s checks and balances to the Trump administration.”
In a further tweet, Mr Trump appeared to praise Ms Pelosi, saying: “In all fairness, Nancy Pelosi deserves to be chosen Speaker of the House by the Democrats. If they give her a hard time, perhaps we will add some Republican votes. She has earned this great honour!”
The House loss means Mr Trump is likely to face investigations into his tax returns, his businesses and his administration by Democratic lawmakers.
His legislative agenda, including a proposal for a middle-class income tax cut, is likely to be stalled.
But a defiant Mr Trump called the result a “big win” and is due to hold a news conference at the White House at 11.30 am (4.30pm GMT).
The American President tweeted: “Received so many Congratulations from so many on our Big Victory last night, including from foreign nations (friends) that were waiting me out, and hoping, on Trade Deals.
“Now we can all get back to work and get things done!”
Despite losing the House, Mr Trump remained upbeat and hailed his “tremendous success” and even praised himself as a “magic man” for taking a majority in the Senate because the incumbent party typically loses ground in the mid-terms.
The Democrats had never looked likely to win control of the Senate and in the event they fell short of a tidal wave of voter support that would have given them that.
A Senate majority would have allowed Democrats to apply even firmer brakes on Mr Trump’s policy agenda and given them the ability to block any future Supreme Court nominees.
However, the party will still be able to head House committees that can investigate the president’s tax returns, possible business conflicts of interest and links between his 2016 election campaign and Russia.
The Democrats could also force Trump to scale back his legislative ambitions, possibly dooming his promises to fund a border wall with Mexico, pass a second major tax-cut package, or carry out his hardline policies on trade.